KR19990007915A - Coarse and fine polyamide fiber and its manufacturing method - Google Patents

Abstract

It has excellent stability in the weaving process, has a small and natural unevenness due to dyeing contrast, and has a slight unevenness on the fabric surface. This good material and product are disclosed.

The nonuniform thickness in the longitudinal direction of the polyamide-based multifilament of the present invention is from 5% to 20% at U-stanal U%, and the standard deviation of the stress at 40% elongation point of the stress-strain curve at 20 cm of the sample is 0.3 g / d. The coarse and fine yarns described below, and the above-mentioned coarse yarns are flammable between the feeding roller and the stretching roller in low magnification of the polyamide-based multifilament unstretched yarn having the birefringence Δn of 20 × 10 ⁻³ or less. It extends | stretches by ship and manufactures by thermosetting at 100 degreeC-200 degreeC.

Description

Coarse and fine polyamide fiber and its manufacturing method

Conventionally, polyamide fibers have been produced in large quantities for medical, industrial, and interior use because of their excellent fiber properties. However, these polyamide fibers, especially fibers obtained from nylon 6, 66, etc., lacked a dry feeling like polyester, which is another general fiber, and had a smooth feeling. As a method of reducing this smooth feeling, an attempt by a thick thin thread could be made.

Conventionally, coarse polyamide fibers are known from Japanese Unexamined Patent Publications No. 42-22576 and Japanese Unexamined Patent Publications No. 44-7744 as generating melt fractions by using abnormal flow in the spinning metal portion. In addition, Japanese Unexamined Patent Publication No. 44-15573 discloses a method in which a polyamide-based polymer is mixed with an object that is incompatible with it and spun into a stress range where melt fractions occur. In addition, Japanese Patent Laid-Open No. 55-122017 discloses a coarse thread composed of a mixed composition of polyester and polyamide. In addition, Japanese Patent Application Laid-Open No. 58-36210 discloses a method in which a polyamide and a thermoplastic polymer having a secondary transition point temperature of 80 ° C or more are mixed and spun and have a low magnification. However, all of the above-described methods are inferior in stability in the weaving process, and breakage of thread is likely to occur, and continuous production is difficult.

In addition, Japanese Patent Laid-Open No. 63-211335 discloses a polyamide unstretched yarn which is heat treated at 110 ° C to 200 ° C to make crystallization 35% or more, and then stretched at a low magnification of 1.2 to 3.0 times to have a thick cross-sectional area in the fiber axis direction. Although a thin thread is disclosed, only a long length in which the thickness unbalance cycle length of the multifilament longitudinal direction ranges from several tens of centimeters to several meters is obtained. Was obtained, but the product value was insufficient due to the weak color contrast due to dyeing and the poor color fastness.

The present invention relates to a polyamide-based coarse multifilament having a dry feeling, a smooth texture, having a short cycle length by dyeing, and excellent in color fastness.

1 is an example of the stretching apparatus which concerns on this invention for manufacturing a thick thin thread using an unstretched chamber.

Fig. 2 is an example of the weaving device according to the present invention for producing coarse and thin yarns by direct radial stretching.

In the drawing, (1,10) is an unstretched chamber, (2) is a flat roller, (3,11) is a first derry roller (supply roller), (4,12) is a fluid turning nozzle, (5,13) ) Denotes the second derry roller (stretch roller), (6) the third derry roller, (7, 14) the coarse and thin thread, (8) the radiating metal part, (9) the lubrication device, respectively. .

The present invention provides a material having a short period of time by dyeing, and having a natural unevenness and fine unevenness on the fabric surface. I want to get. Furthermore, it is to provide a material and a product having good dyeing fastness.

It is an object of the present invention that the thickness unevenness in the longitudinal direction of a polyamide-based multifilament is 5-20% in the ustanal U%, and the standard deviation of the stress at 40% elongation point of the stress-strain curve at 20 cm of the sample is 0.3. It can achieve with the coarse thin polyamide fiber which is characterized by g / d or less.

In the present invention, U% is 5 to 20%, and the fabric using the polyamide fiber described above has a light and dark contrast due to dyeing and a natural unevenness, and also has a slight unevenness on the surface of the fabric. Therefore, a dry and reduced material is obtained visually and tactilely. Usutanormal U% becomes like this. Preferably it is 6-18%.

Here, it is preferable that the number of fluctuation peaks of 4% or more of thickness is 10 or more / m (real length) with the chart of Ustar normal U%. More preferably, it is 15 pieces / m (real length) or more. By more than 4% of thickness fluctuation, a more effective shade of light is obtained, and the presence of a large number gives a smooth elegant dry feeling.

In Ustar U%, it is preferable that the relationship between 1/2 night (H value) and normal (N value) is H / N ≦ 0.8. More preferably, it is less than 0.6. This is to reduce the 1 / 2-night value of the Ustar U% and to eliminate the long and large thickness unevenness in which the cycle length in the longitudinal direction of the multifilament is from several tens of centimeters to several meters.

In the present invention, it is necessary that the standard deviation of 10 times of repeated measurement times of the 40% elongation point stress of the stress-strain curve at the sample length of 20 cm of the polyamide-based multifilament is preferably 0.3 g / d or less. Is 0.2 g / d or less. More preferably, it is good to be less than 0.15. When the above standard deviation is 0.3 g / d or less, the cycle length of the thick and thin is substantially 20 cm or less of the sample length, and the thick and thin portions are mixed in the cross-sectional direction of the multifilament.

In the present invention, it is preferable that the secondary yield point stress is 0.6 g / d or more, and the elongation at break is 60 to 200% in a stress-strain curve at 20 cm in sample length of the polyamide-based multifilament. More preferably, the secondary yield point stress is 0.8 g / d or more and the elongation at break is 80 to 160%. More preferably, the secondary yield point stress is 0.9 g / d or more and the elongation at break is 90 to 140%. When the yield point stress is 0.6 g / d or more, even if the total needles of the polyamide-based multifilament are smaller, it is possible to suppress permanent distortion in the knitting process and is effective. In addition, by setting the elongation at break to 60 to 200%, the fluff in the knitting process is suppressed, and a dark tone contrast with a short cycle length due to dyeing can be obtained, resulting in a natural unevenness.

In the present invention, the 160 ° C dry heat shrinkage of the polyamide multifilament is preferably 10% or less. More preferably, it is 9% or less. More preferably, it is 8% or less. By making the 160 ° C dry heat shrinkage rate 10% or less, more excellent dyeing fastness is obtained.

Next, the manufacturing method of this invention is demonstrated.

The polyamide fiber having a coarse and thin thickness of the present invention has a low refractive index of polyamide-based multifilament unstretched yarn having a birefringence Δn of 20 × 10 ⁻³ or less, so as to produce a coarse thread, between the feed roller and the stretch roller. It is obtained by burning at and stretching to 1.5 to 2.5 times, and thermally setting at 100 ° C to 200 ° C.

In particular, it is extremely effective in obtaining the coarse thread with short cycle length of the polyamide fiber which was conventionally difficult. Moreover, it is extremely effective in obtaining the coarse thread which a thick part and a thin part are mixed in the cross-sectional direction of a multifilament.

Here, the birefringence Δn of the polyamide-based multifilament unstretched yarn is set to 20 × 10 ⁻³ or less to suppress longitudinal swelling due to moisture absorption of the polyamide-based multifilament unstretched chamber, thereby achieving stable quality in mass production. You can get it.

In addition, although the draw ratio is generally set arbitrarily within the range of the residual elongation of the polyamide-based multifilament unstretched yarn, the present invention is to produce a coarse thread in which a thick portion and a thin portion are substantially mixed, Low magnification stretching in the range of 1.5 to 2.5 times. By setting it as said range, the position of an extension starting point can be fluctuate | varied minutely in the vicinity of a heat set apparatus, and / or the inlet part of a heat set apparatus. Here, it is preferable that the surface temperature of a supply roller shall be 80 degrees C or less. More preferably, it is 70 degrees C or less, More preferably, it is 50 degrees C or less.

This is because the lower the surface temperature of the feed roller is, the position of the starting point of stretching can vary slightly in the vicinity of the heat set apparatus and / or the inlet of the heat set apparatus within a narrow range.

As the method of flammable, the conventionally well-known temporary research can be used. In particular, a fluid swing nozzle is suitably used. Fluid turning nozzles are extremely small in damage to thread threads running the drawing zone, and have very little thread breakage even in the case of obtaining thick and thin threads by high speed weaving. . Although the form of the yarn of this invention obtained in this way mainly has the thick and thin part finely divided by the short pitch, the flammable crimp is hardly seen.

That is, according to the method of the present invention, in the low-stretching drawing, the twisting zone and the ballooning are generated in the thread which is running with the fluid turning nozzle at a drawing stress of 0.3 to 0.6 g / d. By twisting by twisting, it gives a fine random skew deformation in the longitudinal direction of the thread-forming single fiber, and the thread on the downstream side of the fluid turning nozzle is released, but the threading Coarse thread in the longitudinal direction and intermittent direction of the multifilament, because the intermittent contact with the heat set device and the elongation start position fluctuate minutely in the vicinity of the heat set device and / or within the narrow range of the heat set device inlet. The real part of this is the microdispersion change. For this reason, the short coarse thread whose cycle length is less than 20 cm is obtained without being influenced by the length of a drawing area. As a result, the real stain (Uster stain U%) becomes small, and the dark tone contrast with a long cycle length at the time of dyeing is greatly reduced, but a dark tone contrast with a short period length can be obtained.

As a result, the effect of a faintly white pattern is obtained, and a natural unevenness is obtained. As described above, in order to obtain a thick thin thread having a short cycle length, the action of flammable and ballooning is important. In order to stably provide this flammability and ballooning, it is preferable to use a dead-end guide before and behind a fluid turning nozzle.

In this invention, although the method of a heat set is not specifically limited, It is preferable to set it as a tension heat set using a heat drawing roller, a heating hotplate, a hot fin, etc. as a heat set apparatus. The tension heat set is preferable because the relaxation of the molecular chain at the time of thermal set is suppressed and the washing fastness at the time of washing the dyed cloth can be greatly improved. Although the method of a tension heat set is not specifically limited, A contact heating or non-contact heating heating plate can be used. Alternatively, the hot drawing roller is used as the fabric surface, and the friction between the thread and the roller surface is reduced to low friction. And by using hot fins on the surface of the fabric.

It is preferable to make a heat set temperature into 100 to 200 degreeC. More preferably, it is 120 degreeC-160 degreeC. Here, the heat set temperature is the surface temperature of the heat set device in contact with the thread in the contact type heat set device, and the atmosphere temperature of the thread passing portion in the non-contact heat set device.

Next, the preferable manufacturing method of this invention is demonstrated using drawing.

FIG. 1 shows an example of a manufacturing method of obtaining a coarse thread by using an unstretched chamber wound up by melt spinning once. In the unstretched chamber 1 having a birefringence of 20 × 10 ⁻³ or less, the first roller roller 3 (which is a supply roller) and the second roller roller 5 (stretch) through the thin roller 2. Between the rollers) and using the fluid turning nozzle 4 having an air pressure of 0.5 to 5 kg / cm < 2 >, while performing ballooning in the traveling thread, the drawing ratio is reduced to 1.5 to 2.5 times, and then the second derry roller ( 5) and heat set at 100 ° C to 200 ° C, and then wound as a thick, thin thread 7 past the third derry roller 6.

FIG. 2 shows an example of a manufacturing method for obtaining a coarse yarn by spinning directly by spinning directly without winding the unstretched yarn melt-spun. After the oil is supplied to the unstretched chamber 10 having a birefringence index of 20 × 10 ^-3 or less from the spinning metal part 8 by the oil supply device 9, the first delivery roller 11 (which is a supply roller) ) And the second derry roller roller 13 (which is a drawing roller) using a fluid turning nozzle 12 having an air pressure of 0.5 to 5 kg / cm 2, while generating a ballooning in the traveling thread, The film is stretched at a low magnification of 2.5 times, and subsequently thermally set at 100 ° C. to 200 ° C. with the second derry roller 13, and then wound up as a coarse thread 14.

The polyamide in the present invention is nylon 6, nylon 66, nylon 46, nylon 9, nylon 610, nylon 11, nylon 12, nylon 612 or the like or a compound having an amide-forming functional group such as laurolactum, And copolymerized polyamides containing copolymerization components such as sebacic acid, terephthalic acid and isophthalic acid. Particularly preferred among these are nylon 6 and nylon 66.

Examples of the polyamide fiber of the present invention include polyacrylic acid sodium, polyNvinylpyrrolidone, polyacrylic acid and its copolymers, polymethacrylic acid and its copolymers, polyvinyl alcohol and its copolymers, crosslinked polyethylene oxide polymers, and the like. It may contain the moisture absorption and the absorbent material, and general-purpose thermoplastic resins such as polyamide, polyester, polyolefin and the like without impairing the object of the present invention. In addition to the pigments such as titanium oxide and carbon black, conventionally known antioxidants, colorants, light agents, antistatic agents and the like may be added.

Here, the cross-sectional shape of the polyamide fibers may be not only round but also known polyhedral, H, π, C, flat, and flat multileafed shapes. In addition, only mixed fibers or composite fibers of polyamide with other melt-spinable thermoplastic polymers may be used. The fabric form may be appropriately selected depending on the purpose of the fabric, knitting, nonwoven fabric, and the like. As the light and dark contrast due to dyeing has a small and natural unevenness and a slight unevenness on the fabric surface, a visual and tactile dry material is obtained.

Next, the calculation method of the evaluation value in this invention is demonstrated.

① U%: The thickness unevenness in the longitudinal direction of the multifilament is measured by USTER TESTER M0NIT0R C (manufactured by Zellweger USTER). 8m / min of thread speed, TWIST Z l.5, YARN TENTI0N 1.5, EVALUTI0N TlME 1 minute, RANGE 100%, the measurement mode measures the average deviation rate U% at normal (N) and 1/2 night (H) At the same time, the waveform is recorded in the chart. The measured value measures three arbitrary places of a sample, and uses the average value.

From the normal chart, the number of peaks of fluctuation in thickness of 4% or more is measured to calculate the number of peaks per 1m of the actual length.

② Standard deviation of elongation and 40% elongation point stress: Elongation is measured by an Instron tensile tester (TENSILON UTM-III-100 manufactured by TOYO BALDWIN) according to JIS-L1013. A stress-strain curve is obtained at a sample length of 20 cm and a tensile speed of 20 cm / min. The stress-strain curve is calculated from the separately measured fineness, and the average value of 10 measurements is repeated. Further, a 40% elongation point stress is calculated from the stress-strain curve obtained here, and the standard deviation of the stress in 10 measurements is repeatedly calculated.

(3) Secondary yield point stress: The second yield point tension is obtained from the stress-strain curve of the second term, calculated from the fineness measured separately, and the average value of 10 measurements is repeated.

(4) Dry heat shrinkage: According to JIS-L1013 A method, it was measured under the following conditions. After a failed sample was prepared with a checker, after 2 hours of deflation and humidity, a 1/30 (g / d) load was applied, and after 30 seconds, the sample length was measured to L ₀ . do. The sample is placed in an oven-type dryer at both ends in a free state and heat-treated at 160 ° C. for 20 minutes. Subsequently, the sample after dry heat processing is taken out of oven, it is left to cool indoors and humidity is performed for 2 hours indoors. A load of a second 1/30 (g / d) is applied to this cold / humidity sample, and after 30 seconds, the sample length is measured and referred to as L. Dry heat shrinkage is calculated by the following equation.

Dry Heat Shrinkage (%) = [(L ₀ -L) / L ₀ ] × 100

The measured value measures five arbitrary places of a sample, and uses the average value.

(5) Non-shrinkage rate: It measures by the method of JIS-L1013A method.

(6) Density: Measured by the density balance tube method of JIS-L1013.

⑦ Birefringence: It is measured by a compensator method using a BH-2 polarizing microscope manufactured by 0LYMPUS.

Humidity conditions of ①∼⑦ are all 20 ± 2 ℃ and relative humidity is 65 ± 2%.

(8) Wash fastness: After the treatment according to the method described in JIS08L0844 "Dyeing fastness test for washing" method A-2, the degree of fading before and after washing is graded by gray scale according to the following criteria.

5th grade; No fading is recognized at all.

4th grade; Almost no fading

Level 3: A little fading is recognized.

Level 2: Fading is recognized.

Level 1: Severe fading

⑨ Light fastness: According to JIS-L0842 "Dye fastness test by carbon arc light". 10-hour irradiation is grade 3, 20-hour irradiation is grade 4, and 40-hour irradiation is grade 5, and the fading of the sample is graded by grayscale based on the fading of the blue scale.

The dyeing treatment conditions are as follows.

Refinement condition

1 g / liter soda ash

Gram-up US '20 (product made by Sanyo Okasei Co., Ltd.) 0.5 g / liter

Yokbi 1:50

Temperature X time 60 degrees Celsius * 60 minutes

Preparation of dyeing conditions

Dye (miring acid acid dye: acid company) PH-500 0.5 g / liter

Nylosan Gold. Yellow N-4RL 0.5% owf leveling agent: Newpon TS-400 3% owf

Nylosan Red N-GZN 0.5% owf bath ratio 1:20

Nylosan Blue N-GFL 167% l.0% owf Temperature × Time 98 ℃ × 60 minutes

FIX processing condition

A fixing agent: Sunlife TA-50K (made by Japan-China Chemical Co., Ltd.) 5% owf

Acetic acid 0.5 g / liter

Bathe 1:20

Temperature X time 80 degrees Celsius * 20 minutes

Next, the present invention will be described in detail by way of examples.

Example 1

A nylon 6 polymer having a sulfuric acid relative viscosity of 2.63 was melt spun at a spinning temperature of 260 ° C. at a spinning speed of 800 m / min to obtain a multifilament unstretched yarn having 220 deniers, 24 filaments, and a birefringence of 12 × 10 ⁻³ . The unstretched yarn described above was stretched at a stretching speed of 800 m / min with the stretching apparatus of FIG. Table 1 shows the stretching conditions and the quality of the yarns described above.

Experiment No. 1 to 4

Experiment No. As for the thick thin thread of this invention of 1-4, U% of the thickness nonuniformity of the longitudinal direction of a multifilament was 5 to 17%, and 160 degreeC dry heat shrinkage was 3 to 8%. In addition, a 40% elongation point stress of the stress-strain curve was calculated at a sample length of 20 cm, and the standard deviation of the stress in 10 repeated measurements was as small as 0.03 to 0.27 g / d.

Next, the multifilament coarse thread of Table l was woven into a plain fabric at a fabric density of 90 × 75 pieces / inch, and a natural fabric was set in a 180 ° C. tenter, and refined, dyed with an acid dye, FIX treatment, and 160 ° C. The finishing set was performed in the tenter, and the fabric sample was prepared.

The fabric sample had fine unevenness on the surface of the fabric, and thus, the fabric sample was rich in dryness and stiffness. Further, as the fastness of dyeing, both the fastness to washing and light fastness were obtained at level 4 or higher. In addition, the difference in shade due to dyeing was expressed, and a natural unevenness of span was obtained by synergistic effect with surface irregularities.

Comparative Example 1

Experiment No. Under the stretching condition of 1, the fabric sample was stretched without using the fluid swing nozzle.

Table 1 shows the stretching conditions and the quality of the yarns described above. In the coarse and thin yarn of the comparative example 1, the thickness nonuniformity U% of the longitudinal direction of the multifilament was 20%, and the standard deviation of 40% elongation point stress was 0.5 g / d, and it was extremely uneven.

The fabric sample has unevenness on the surface of the fabric and is a product full of dry feeling, a feeling of stiffness for this, but, as for the color fastness, washing fastness, light fastness are all third grade, and fading is recognized, and it is almost a practical lower limit Was. In addition, the cycle length of the light-difference tea and the thick thin thread by dyeing are large, and fall in aesthetics, and it was inferior to the quality as a product.

Comparative Example 2

Experiment No. Under the stretching condition of 1, the heat set temperature (stretching roller temperature) was stretched at 30 ° C. to prepare a fabric sample.

Table 1 shows the stretching conditions and the quality of the yarns described above. As for the thick thin thread of the comparative example 2, the thickness nonuniformity U% of the longitudinal direction of a multifilament was 18%, and the standard deviation of 40% elongation point stress was 0.4 g / d, and the imbalance was large. Moreover, 160 degreeC dry heat shrinkage was as high as 13%, and density was as low as 1.130 g / cm <3>. For this reason, fabric samples have irregularities on the surface of the fabric and are rich in dryness and crumbness. However, dyeing fastnesses of the washfastness and lightfastness are both 2 to 3 grades and have not endured practical use. In addition, since the difference in color by the dyeing is very long, it was inferior to the quality as a product.

Comparative Example 3

Experiment No. Under the drawing conditions of 1, the supply roller temperature was extended to 90 ° C and the heat set temperature (extension roller temperature) to 210 ° C to prepare a fabric sample.

Table 1 shows the stretching conditions and the quality of the yarns described above. The coarse thread of the comparative example 3 was a product whose thickness nonuniformity U% of the multifilament length direction was 2% small, and the uneven feeling was not acquired in the fabric surface, and for this reason, it was a product lacking a dry feeling and a crumbly feeling. In addition, the dyeing fastnesses of the wash fastness and light fastness were both the second to third class and did not endure practical use. Furthermore, the difference in color by the dyeing was insufficient, and it was inferior to the quality as a product.

Experiment No.1 Experiment No.2 Experiment No.3 Experiment No. 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Unstretched birefringence (Δn × 10 ^-3 ) 12 12 12 12 12 12 12 Feed roller temperature (℃) 40 60 50 30 40 30 90 Air pressure of turning nozzle (㎏ / ㎠) 2.0 1.6 3.0 2.5 none 2.0 2.0 Stretch ratio (times) 2.0 2.0 2.2 2.5 2.0 2.0 2.0 Heat set temperature (stretching roller temperature) (℃) 140 120 170 150 140 30 210 Drawn Roller Surface Mirror Mirror Mirror Mirror Mirror Mirror Mirror Drawing speed (m / min) 800 800 800 800 800 800 800 Strength (g / d) 3.5 2.8 2.3 4.0 3.5 3.0 2.3 Elongation (%) 120 140 95 83 120 120 30 Standard Deviation of 40% Elongation Point Stress (g / d) 0.10 0.27 0.25 0.03 0.50 0.40 0.04 Secondary blessed stress (g / d) 1.52 0.90 1.86 1.25 0.45 0.60 0.40 Non-shrinkage rate (%) 5 10 5 8 6 18 2 160 ℃ dry heat shrinkage (%) 3 8 3 7 5 13 One Birefringence (Δn × 10 ^-3 ) 35 31 36 45 27 25 30 Density (g / cm 3) 1.134 1.132 1.135 1.136 1.134 1.130 1.137 Seal stain (Usutanormal U%) 8 15 17 5 20 18 2 Number of fluctuation peaks (pieces / m) 23 25 20 17 9 5 3 H / N ratio 0.25 0.70 0.60 0.40 0.95 0.92 0.52 Wash fastness (class) 4 to 5 4 4 4 to 5 3 2-3 2-3 Light fastness (class) 4 to 5 4 to 5 4 to 5 4 to 5 3 2-3 2-3

Example 2

The sulfuric acid relative viscosity of 2.63 nylon 6 polymer was melt spun at the spinning temperature of 260 ° C. at a spinning speed of 1000 m / min using the direct spinning apparatus of FIG. 2, and then stretched twice to obtain 110 denier and 24 filament coarse filaments. Got. Table 2 shows the stretching conditions and the quality of the yarns described above. In addition, the birefringence rate of the unstretched yarn wound and melted at a spinning speed of 1000 m / min and stretched was 16 × 10 ⁻³ .

Experiment No. 5 to 6

Experiment No. As for the thick thin thread of this invention of 5-6, U% of the thickness nonuniformity of the longitudinal direction of a multifilament was 9 to 12%, and 160 degreeC dry heat shrinkage rate was 3 to 8%.

Further, a 40% elongation point stress of the stress-strain curve was calculated at a sample length of 20 cm, and the standard deviation of the stress in 10 repeated measurements was as small as 0.05 to 0.15 g / d.

Next, the multifilament coarse thread of Table 2 is woven into a plain fabric at a fabric density of 90 × 75 pieces / inch, and is set into a natural fabric with a 180 ° C. tenter, followed by refining, dyeing with acid dyes, FIX treatment, and finishing set. Four cloth samples were prepared.

The fabric sample had fine unevenness on the surface of the fabric, and thus, the fabric sample was rich in dryness and stiffness. Further, as the fastness of dyeing, both the fastness to washing and light fastness were obtained at level 4 or higher. In addition, the difference in shade due to dyeing was expressed, and a natural unevenness of span was obtained by synergistic effect with surface irregularities.

Comparative Example 4

Experiment No. Under the direct radiation drawing condition of 5, the fabric sample was stretched without using the fluid turning nozzle. Table 2 shows the stretching conditions and the quality of the yarns described above. The pore yarn of Comparative Example 4 had a thickness unevenness U% of the multifilament in the longitudinal direction of 22%, a standard deviation of 40% elongation point stress of 0.4 g / d, and a 160 ° C dry heat shrinkage rate of 5%.

The fabric sample has irregularities on the surface of the fabric and is a product full of dry feeling, a feeling of stiffness for this, but as color fastness, washing fastness, light fastness are all three grades, and fading is admitted, and it is almost a practical lower limit Was. In addition, the difference in color and color, and the cycle length by the dyeing are large and lack of aesthetics, which is inferior to the product quality.

Comparative Example 5

Experiment No. Under the direct radiation drawing condition of 5, the heat set temperature (stretching roller temperature) was stretched at 25 ° C. to prepare a fabric sample.

Table 2 shows the stretching conditions and the quality of the yarns described above. As for the thick thin thread of the comparative example 5, the thickness nonuniformity U% of the longitudinal direction of a multifilament was 25%, the standard deviation of 40% elongation point stress was 0.4 g / d, and 160 degreeC dry heat shrinkage rate was 12%.

The fabric sample had unevenness on the fabric surface and was rich in dryness and crumbness for this purpose, but it was a rough texture. In addition, as dyeing fastness, washing fastness and light fastness were all 3 grades, fading was recognized, and it was almost the practical minimum. In addition, it was inferior to the quality as a product because the difference in color by light dyeing and the thick and thin cycle length were large and lacked in aesthetics.

Experiment No. 5 Experiment No. 6 Comparative Example 4 Comparative Example 5 Unstretched birefringence (Δn × 10 ^-3 ) 16 16 16 16 Feed roller temperature (℃) 25 50 25 25 Air pressure of turning nozzle (㎏ / ㎠) 3 2 none 2 Stretch ratio (times) 2.0 1.8 2.0 2.0 Heat set temperature (stretching roller temperature) (℃) 180 150 180 25 Drawn Roller Surface Mirror Mirror Mirror Mirror Drawing speed (m / min) 2000 1800 2000 2000 Strength (g / d) 3.3 3.5 3.0 2.8 Elongation (%) 80 120 110 120 Standard Deviation of 40% Elongation Point Stress (g / d) 0.05 0.15 0.4 0.4 Secondary Yield Point Stress (g / d) 1.15 0.9 0.58 0.50 Non-shrinkage rate (%) 5 14 5 18 160 ℃ Dry Heat Shrinkage (%) 3 8 5 12 Birefringence (Δn × 10 ^-3 ) 40 35 28 25 Density (g / cm 3) 1.135 1.134 1.135 1.132 Seal stain (Usutanormal U%) 9 12 22 25 Number of fluctuation peaks (pieces / m) 24 20 8 6 H / N ratio 0.20 0.50 0.87 0.93 Wash fastness (class) 4 to 5 4 3 3 Light fastness (class) 4 to 5 4 to 5 3 3

Example 3

The nylon 6 polymer having a sulfuric acid relative viscosity of 2.63 was changed at a spinning temperature of 260 ° C. to obtain another 220 denier, 24 filament unfinished yarn having a birefringence Δn. In the unstretched chamber described above, a hot plate having a length of 20 cm and a temperature of 150 ° C. is installed between the fluid swing nozzle 4 and the second derry roller 5 using the stretching device of FIG. 1 (heat set temperature 150 ° C.). Then, the first derive roller (3) and the second derry roller (5) were stretched by non-heating to obtain a multifilament coarse thread. Moreover, the surface temperature of the 1st berry roller 3 measured with the surface thermometer was 30 degreeC, and the surface temperature of the 2nd berry roller 5 was 45 degreeC. Table 3 shows the stretching conditions and the quality of the yarns described above. Next, the multifilament coarse thread of Table 3 is woven into a plain fabric with a fine density of 90 x 75 pieces / inch, a natural fabric is set in a 180 ° C tenter, refined by dyeing, dyeing with an acid dye, FIX treatment, The finishing set was performed by the 160 degreeC tenter, and the fabric sample was produced.

Experiment No. The fabric samples of 7, 8 had fine unevenness on the surface of the fabric, and because of this, the product was rich in dryness and crumbness. Further, as the fastness of dyeing, both the fastness to washing and light fastness were obtained at level 4 or higher. In addition, the difference in shade due to dyeing was expressed, and a natural unevenness of span was obtained by synergistic effect with surface irregularities.

Experiment No. The fabric sample of 9 had fine irregularities on the surface of the fabric, and was thus a product rich in dryness and crumbness. Wash fastness and light fastness were grade 4 and were able to endure practically enough.

Comparative Example 6

In the manufacturing method of Example 3, the spinning speed was changed and the unstretched yarn of birefringence (DELTA) n was 22x10 <^-3> . Said unstretched room was extended | stretched on extending | stretching conditions shown in Table 3, and the extending | stretching room of the comparative example 6 was obtained. Table 3 shows the quality of the yarn and the fabric samples of the drawing room.

Since the thread stain was small at 4% in the Ustanormal U%, the unevenness of the fabric surface was insufficient, and a dry feeling and a feeling of stiffness were not obtained because of this. Furthermore, the difference in color by dyeing was small, washing fastness was grade 3, fading was recognized, and it was almost the practical minimum. Light fastness was grade 4 and endured practical enough. In addition, the dry heat shrinkage rate was high, and the texture of the fabric sample was slightly hard because of this.

Comparative Example 7

Experiment No. It extended by the extending | stretching conditions shown in Table 3 using the unstretched room of 7, and obtained the stretched room of the comparative example 7. Table 3 shows the quality of the yarn and the fabric samples of the drawing room. The fabric sample of Comparative Example 7 had unevenness on the surface of the fabric, which is rich in dryness and stiffness. However, the color difference between the dyeing and the thick and thin cycle length are very large and lack of aesthetics. Further, the fastness of washing was low to second grade and light fastness to third grade, and it did not endure practical use. In addition, since the secondary yield point stress is low, there is a problem in that permanent warp is likely to remain during weaving and cloth wearing.

Experiment No. 7 Experiment No.8 Experiment No.9 Comparative Example 6 Comparative Example 7 Unstretched birefringence (Δn × 10 ^-3 ) 12 15 12 22 12 Feed roller temperature (℃) 30 30 30 30 30 Air pressure of turning nozzle (㎏ / ㎠) 1.7 2.5 2.0 3.0 3.0 Stretch ratio (times) 1.8 2.2 2.0 2.7 1.4 Heat set temperature (stretching roller temperature) (℃) 150 150 150 150 150 Drawn Roller Surface Mirror Mirror Mirror Mirror Mirror Drawing speed (m / min) 800 800 800 800 800 Strength (g / d) 2.5 3.7 2.6 2.7 2.8 Elongation (%) 140 70 150 50 210 Standard Deviation of 40% Elongation Point Stress (g / d) 0.15 0.05 0.10 0.04 0.60 Secondary Yield Point Stress (g / d) 0.9 1.4 0.7 1.8 0.5 Non-shrinkage rate (%) 13 14 12 18 8 160 ℃ dry heat shrinkage (%) 8 9 7 12 4 Birefringence (Δn × 10 ^-3 ) 35 45 36 48 28 Density (g / cm 3) 1.131 1.134 1.134 1.137 1.128 Seal stain (Usutanormal U%) 14 9 10 4 25 Number of fluctuation peaks (pieces / m) 27 20 22 9 14 H / N ratio 0.64 0.43 0.57 0.34 0.97 Wash fastness (class) 4 to 5 4 to 5 4 3 2 Light fastness (class) 4 to 5 4 to 5 4 4 3

The polyamide fiber of the present invention has a feeling of dryness and a feeling of stiffness, and a light and dark difference with a short cycle length is expressed by dyeing, so that it has a natural unevenness and has a slight unevenness on the fabric surface. A dry reducing material is obtained, and a material and a product which are excellent in color fastness are provided. The production method is also industrially excellent in stability.

Claims (9)

The thickness unevenness in the longitudinal direction of the polyamide-based multifilament is 5 to 20% at the excellent tanomeric U%, and the standard deviation of the 40% elongation point stress of the stress-strain curve at the sample length of 20 cm is 0.3 g / d or less. Coarse and fine polyamide fiber. The coarse polyamide based fiber according to claim 1, wherein the number of fluctuation peaks of 4% or less is 10 or more / m (real length) in a chart of ustanomal U%. The relationship between 1/2 night (H value) and normal (N value) is H / N≤0.8 according to any one of claims 1 to 2, characterized in that in the ustanonormal U%, Coarse, fine polyamide fiber. The stress-strain curve at a sample length of 20 cm of the polyamide-based multifilament according to any one of claims 1 to 3, wherein the secondary yield point stress is 0.6 g / d or more, and the elongation at break is 60 to 3. Coarse and fine polyamide fiber, characterized in that 2000%. The coarse and fine polyamide fiber according to any one of claims 1 to 4, wherein a 160 ° C dry heat shrinkage ratio is 10% or less. In producing polyamide-based multifilament unstretched yarn having a birefringence Δn of 20 × 10 ⁻³ or less at low magnification to produce a coarse thin yarn, it is combustible between the feeding roller and the stretching roller, drawn at 1.5 to 2.5 times, and stretched from 100 ° C. to Process for producing coarse and fine polyamide fibers, characterized in that the heat set at 200 ℃. 7. The method for producing coarse, fine polyamide fibers according to claim 6, wherein ballooning is imparted between the feed rollers and the stretch rollers by a fluid swing nozzle. 8. The method for producing coarse, fine polyamide fibers according to any one of claims 6 to 7, wherein the surface temperature of the feed roller is 80 ° C or less. The method for producing coarse, fine polyamide fibers according to any one of claims 6 to 8, wherein the heat set is performed on a hot plate.